I am very new at this and I can't afford gym memberships or lots of expensive equipment. I've heard that, in addition to walking, I need to do some strength training. I was wondering if anyone has some ideas on exercises I can do with stuff around the home?

Some of my favorite exercises are bodyweight exercises like push-ups, lunges, and squats. If you have stairs or a few chairs you can do dips as well. With stairs you can even vary the height of your push-ups (experiment with feet on the ground, hands on the stairs - these will be easier; or hands on the ground, feet on the stairs - these will be harder).

To increase weight on these exercises, find a sturdy backpack and load it up with rocks, books, or any other heavy stuff you have around the house. A scale will tell you exactly how much you've put in there so you can keep track of your improvement on the squats, lunges and push-ups. From my experience a backpack doesn't work as well for dips, so when you get better at doing dips from the stairs, try doing them on the parallel bars at the local playground (also a good place to find pull-up bars!).

If you want to invest in some inexpensive equipment, try to find the Iron Gym pull-up bar. I found mine at CVS for something like $25. Even if you can't do a pull-up yet, just doing one is a great goal to shoot for and in the meantime you can use it for hanging knee raises (I prefer these to crunches for my abs).

Checkout yard sales, 2nd hand stores.
Another source is a group on Yahoo called Freecycle. People list things they have or things they want, the mission is to keep usable things out of the dump. It's all free. The network is broken down into local areas.

If you get into exercise videos, there's a website called VideoFitness that has a swap section, some people offer the videos for free... you have to send them the postage.

Speaking of free, sometimes you can "swap" out what you need from somebody else, if you get lucky enough to have something they want too. Or at least pay the difference and if you get really savvy at it, you can get LOTS of stuff free. That is how my brother got his weight set and his stereo system

yoga moves such as the plank and downward facing dog are great strength builders and muscle toners. It's a part of my routine every morning including wall pushups (I'm trying to build up to regular pushups, which is why building upper body strength is a huge goal of mine right now).

Thanks everyone for the advice. I managed to snag an air-walker from freecycle, so I'll give that a go. Also today I started my excercise routine.

I didn't want to do too much since it was the first time I'd excercised in quite a long time. I just danced for about ten minutes to warm up, then did twenty sit-ups, some hip flexors (ten on each leg) and about three 30sec superman's (or should I call that supermen lol), finishing up with some stretches.

That SparkPeople website has proved invaluable. I intend to alternate days where I do cardio and strnghth training - I seem to remember reading somewhere that you shouldn't do weights two days in a row?

Anyway, I will vary the excercises, starting out slow and adding reps each time. I'll be fit and healthy in no time (speaking hopefully )

The only reason you shouldn't do weights two days in a row is if you were really taxing your nervous system — which if you're just starting out won't be a problem. Because you're still new to it, your nervous system will start to adapt fairly quickly (which is why beginners experience the biggest gains in terms of strength), and if you're not using weights that you can't lift more than 8 times in a set you're not going to be taxing your muscles enough that you can't lift again the next day.

Long story short, unless you've been lifting for longer than 6 months - a year and you're lifting weights you can't move more than 8 times in a set, don't get discouraged from lifting as often as you want!